Field
The present disclosure relates generally to a semiconductor package with a barrier for a radio frequency (RF) absorber and manufacturing methods therefor.
Description of the Related Art
Various types of semiconductor packages may include very high frequency RF integrated device dies (e.g., transmitter or receiver front ends) that may cause interference with or otherwise disturb electronic components outside the package. Package lids may be used to contain the RF emissions emitted from within a package, such as, for example, from within packages having high frequency device dies (e.g., E-band or other high frequency devices). While such lids can advantageously shield surrounding circuit components from electromagnetic interference, the lids may also cause unpredictable and electrically disruptive cavity resonances inside the package, which can disturb the circuit components therein. To resolve these potential problems, RF absorbers may be disposed inside the package to dampen and/or absorb the RF waves emitted by the device dies in the package. However, the materials which form portions of some RF absorbers may release gases such as hydrogen and sulfur (among other gases) in sealed environments. Such outgassing can damage active components in various types of integrated device dies. To protect the device dies from the outgassing, a gettering material may be disposed inside the cavity of the package.
However, gettering materials are expensive, and their hydrogen removal efficiency can decrease over time. As a result, the production of high frequency devices in large quantities can become prohibitively expensive with the incorporation of gettering materials. Moreover, as the hydrogen removal efficiency of the gettering material decreases, the hydrogen outgassed from RF absorbers may eventually contaminate the dielectric materials inside the cavity and degrade the circuit components therein. Accordingly, there is a continuing need for a low cost package housing that effectively shields external components from RF emissions from the package and that that also prevents contamination due to outgassing from the RF absorber.